Snakelike robots could simplify heart surgery

A new snakelike surgical robot, CardioArm, developed by Carnegie Mellon University (CMU), could let a surgeon make one incision when performing a critical heart operation.

The curved robot has a series of joints that automatically adjust to follow the course plotted by the robot's head, providing greater precision than a flexible endoscope can offer, according to researchers.

“It's certainly easier to control," said Robert Webster III, a professor at Vanderbilt University, who works on flexible medical probes but is uninvolved with the CardioArm.

The CardioArm is operated using a computer and a joystick, and has 102 degrees of freedom, three of which can be activated at once, according to the developers. This capability allows it to enter through a single point in the chest and wrap around the heart until it reaches the right spot to, for example, remove problematic tissue.

“The nice thing about [the] design is that each joint follows where you went in space. That's not always possible in other designs,” Webster said. This level of control prevents the probe from bumping into sensitive tissue. The disadvantage of a jointed robot, however, is that it is harder to miniaturize, Webster noted.

The smallest version of the device is 300 mm long and has a diameter of 12 mm. Eventually, the Pittsburgh-based CMU researchers hope to make a robotic snake small enough to enter the bloodstream through a blood vessel, said Marco Zenati, a principal researcher on the CardioArm project and a professor of surgery at the University of Pittsburgh.

Realizing the need for more advanced robots for minimally invasive surgery, Zenati aligned with Howie Choset, known for his work on robotic snakes, and Alon Wolf, founder and director of the Biorobotics and Biometrics Lab at Technion, the Israel Institute of Technology in Haifa, Israel.

Currently, the team has performed successful cardiovascular surgeries on nine pigs and two human cadavers, Choset said.

Cardiorobotics reported that live human trials are slated to begin later this year.